Method for handling containers and a means to carry out a method for selecting a desired position on a stacking target

Apparatus to carry out a method for handling containers in which containers are stacked using a moveable crane with a traveling trolley arranged to lift a container, by moving, lifting and landing said container on a stacking target in a stack including at least one ground container, said method comprising the steps of:

• measuring the horizontal position of the stacking target, said stacking target being the top surface of the uppermost container of the stack, determining the horizontal position of the ground container, comparing the relative positions of said stacking target and said ground container, determining an overlap from the relative positions of said stacking target and said ground container, and determining if the overlap is within predetermined limits, and if so, determining a desired landing position for the container on the stacking target, said landing position being so selected to offset possible stacking errors in the stack, said apparatus comprising:
• a moveable crane, control means for the crane including a memory means, the trolley including a laser sensor means, said trolley arranged with a spreader for holding said container such that horizontal measurements made by said sensor means of distances from said trolley to the stacking target and horizontal measurements of distances from said trolley to the ground container being stored in the memory means to calculate said desired position.